The present invention relates to a high efficiency light, and more particularly to such a high efficiency light which uses LEDs to emit light, and different lenses to amplify the intensity of light from the LEDs.
A regular traffic signal light 7, as shown in FIG. 3, is generally comprised of a reflective lamp shade 71, an incandescent bulb 72 mounted inside the lamp shade 71, and a lens 73 covered on the front open side of the lamp shade 71. This structure of traffic signal light consumes much electric energy, and emits less intensity of light. The lamp shade 71 and the lens 73 cannot greatly amplify the intensity of light emitted from the incandescent bulb 72. FIG. 4 shows a LED type traffic signal light 8 according to the prior art. This structure of LED type traffic signal light 8 comprises a reflective lamp shade 81, a circuit board 82 mounted on the reflective lamp shade 81 and holding a set of LEDs (light emitting diodes) 83, and a hollow rounded lens 84 covered on the reflective lamp shade 81 over the LEDs 83. This structure of LED type traffic signal light 8 consumes less electric energy, however it is still not satisfactory in function. The drawbacks of this structure of LED type traffic signal light is outlined hereinafter.
1. The lens 84 does not effectively amplify the intensity of light passing through. PA0 2. In order to obtain sufficient light, a big number of LEDs must be installed, thereby causing the cost of the traffic signal light unable to be reduced to the desired level. PA0 3. In order to obtain a uniform intensity of light, the quality of used LEDs must be strictly examined. PA0 4. Because the top side 85 of the circuit board 82 does not reflect light from the LEDs 83, downward emitting light rays from the LEDs 83 are wasted (see FIG. 5A). PA0 5. Because light from the LEDs 83 is not well diffused, spots of light are seen from the outside corresponding to the LEDs 83.